/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.iotdb.db.mpp.transformation.dag.column.binary;

import org.apache.iotdb.db.mpp.transformation.dag.column.ColumnTransformer;
import org.apache.iotdb.tsfile.read.common.block.column.Column;
import org.apache.iotdb.tsfile.read.common.block.column.ColumnBuilder;
import org.apache.iotdb.tsfile.read.common.type.Type;

public abstract class BinaryColumnTransformer extends ColumnTransformer {

    protected final ColumnTransformer leftTransformer;

    protected final ColumnTransformer rightTransformer;

    public BinaryColumnTransformer(
            Type returnType, ColumnTransformer leftTransformer, ColumnTransformer rightTransformer) {
        super(returnType);
        this.leftTransformer = leftTransformer;
        this.rightTransformer = rightTransformer;
        checkType();
    }

    @Override
    public void evaluate() {
        leftTransformer.tryEvaluate();
        rightTransformer.tryEvaluate();
        // attention: get positionCount before calling getColumn
        int positionCount = leftTransformer.getColumnCachePositionCount();
        Column leftColumn = leftTransformer.getColumn();
        Column rightColumn = rightTransformer.getColumn();

        ColumnBuilder builder = returnType.createColumnBuilder(positionCount);
        doTransform(leftColumn, rightColumn, builder, positionCount);
        initializeColumnCache(builder.build());
    }

    protected abstract void doTransform(
            Column leftColumn, Column rightColumn, ColumnBuilder builder, int positionCount);

    public ColumnTransformer getLeftTransformer() {
        return leftTransformer;
    }

    public ColumnTransformer getRightTransformer() {
        return rightTransformer;
    }
}
